Punches classified according to the slider drive mechanism include crankshaft punches, crankshaft less punches, toggle punches, friction punches, spiral punches, rack punches, connecting rod punches, and cam punches.
Crankshaft punch
A punch press using a crankshaft mechanism is called a crankshaft punch press. The most common reasons for using a crankshaft mechanism are that it is easy to make, can accurately determine the lower end position of the stroke, and the slider movement curve is basically suitable for various processing. Therefore, this type of stamping is suitable for punching, bending, drawing, hot forging, warm forging, cold forging and almost all other punch processing.
Crankshaft less punch
Crankshaftless punch presses are also called eccentric gear punch presses. Comparing the structure and performance of crankshaft punch presses with eccentric gear press presses, the eccentric gear punch press structure is superior to the crankshaft structure in terms of shaft rigidity, lubrication, appearance, and maintenance. The disadvantage is that the price is higher. When the stroke is long, the eccentric gear type punch is more advantageous, and when the stroke of the special punching machine is short, the crankshaft punch is better.
Toggle punch
A toggle punch that uses a toggle mechanism on the slider drive is called a toggle type punch. This type of punch has a unique slider movement curve in which the slider speed becomes extremely slow near the bottom dead center (measured in comparison with the crankshaft punch). It also accurately determines the position of the lower dead center of the stroke, so this type of punch is suitable for compression processing such as imprinting and finishing. It is most commonly used in cold room forging.
Friction punch
Punch presses that use friction transmission and screw mechanisms on track drives are called friction punch presses. This kind of punch is most suitable for forging and crushing operations. It can also be used for bending, forming, drawing and other processing. It has a versatile function and was widely used because of its low price.
Spiral punch
The use of a screw mechanism on the slide drive mechanism is called a screw punch.
Rack punch
A rack-and-pinion punch machine that uses a rack and pinion mechanism on the slide drive mechanism is called a rack punch. The rack punch has almost the same characteristics as the spiral punch, and its characteristics are roughly the same as those of the hydraulic punch. In the past, it was used for extruding bushings, chips and other items, pressing oil, bundling, and extruding cartridge cases (thinning processing in hot rooms), etc. However, it has now been replaced by hydraulic punches, unless it is extremely special situation.
Connecting rod punch
Punch presses that use various link mechanisms on the slide drive mechanism are called link type punch presses. The purpose of using a link mechanism is to keep the stretching speed within limits during drawing processing while reducing the processing cycle. By reducing the speed change of drawing processing, speed up the approach stroke from the top dead center to the start of processing and the return stroke from the bottom dead center to the dead center, so that it has a shorter cycle than the crankshaft press to increase productivity.
Cam punch
Punch presses that use a cam mechanism on the slide drive mechanism are called cam presses. The characteristic of this punch is that the cam shape can be made appropriately so that the desired slider movement curve can be easily obtained. However, due to the nature of the cam mechanism, it is difficult to convey greater force, so the punch capacity is very small.